▎ 摘　　要

NOVELTY - A metastable composite material comprises a core-shell structure. The core is an aluminum particle coated with a fluorine-containing polymer. The shell is a sulfonated graphene coating layer or a reduced graphene oxide coating layer. USE - Metastable composite material. ADVANTAGE - The metastable composite material has uniform, dense and excellent interface bonding, high utilization rate of active aluminum, excellent heat transfer efficiency, fast energy release, and excellent heat resistance and stability. The preparation process is simple and controllable, and the cost is low, which is suitable for large-area application. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of metastable composite material, which involves (1) adding the aluminum particle dispersion into the fluoropolymer solution, mixing, and separating the solid product to obtain aluminum particles coated with fluoropolymer, (2) dispersing sulfonated graphene or reduced graphene oxide in a solvent to make a dispersion, and (3) adding the fluoropolymer-coated aluminum particles into the dispersion liquid in step (2), mixing, and separating out the solid product to obtain a metastable composite material.